At a recently attended unified communications (UC) conference in San Diego, I made five observations that convinced me that office computers and office phones as we've always known them will be all but extinct within the next ten years (if not much sooner).
Observation #1: At a UC conference where the majority of attendees were business phone system equipment manufacturers and distributors, most every speaker talked not about the importance of desk phones integrating with office computers, they talked about the importance of "critical business applications" working equally well on any "end point" whether that was a desktop computer, smartphone (iPhone or Android) or a tablet computer like an iPad. The main references made to office equipment was the necessity to source good office "docking stations" that employees could drop their tablets and smartphones into when they were actually working in the office.
Observation #2: Through one conference presentation after another, when I looked at the 100+ business executives in the conference audience, at any one time, at least two-thirds were quite busy conducting their normal daily business tapping away on the face of their smartphones and iPads. They would politely look up at the speaker now and then to acknowledge an important speaking point - but then they'd go right back to tapping and swiping their keyless glass tablets and smartphones.
Observation #3: The conference attendees in the audience were all collaborating on work projects with employees back at their offices without talking on the phone. In two and a half days of conference presentations I think I only saw two people ever stop swiping and tapping their phones and tablets because they actually had to step out of the seminar room to speak with someone the old-fashioned way - with their voice.